I’ve had another product from shg.dk fail on me. I’ve learned my lesson about buying their cheapest products, they break to fast. To their defence I must say that their RMA support has been fantastic, so I will continue to do my computer shopping with them. I’ve sent products back two times, and their reaction time has both times been around 3-4 hours. That is they’ve already sent me a replacement 3-4 hours after receiving my parcel. THAT’S VERY FAST! I’ve never experienced a company with such an efficient RMA service. I’ve tried waiting months with other companies. Have I just been lucky or is the service from shg.dk really that good?
Applications for the web
Developing applications for the web requires another way of thinking than developing normal applications. Some patterns change, which can be hard to cope with. This site http://www.phppatterns.com/ has discussions about design patterns and php. This http://www.fluffycat.com/PHP-Design-Patterns/ might also be a good start…
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Music Recording and Low Latency Kernel on Ubuntu Feisty Fawn Part I
I’ve just heard about Ubuntu Studio and got inspired to try and do some music recording 
Well that will require using a low latency kernel, which I haven’t seen in the repositories before. Fortunately Ubuntu Feisty Fawn does have such a kernel in the repositories. I installed it by issuing the following command in a terminal:
$ sudo apt-get install linux-lowlatency linux-restricted-modules-2.6.20-15-lowlatency linux-headers-lowlatency
The update notifier reminded me that I should reboot in order for the changes to take effect. Unlike Windows it gave me the choice of doing it later(not the Windows “restart later” where it has the memory of a fly and bugs you every 5 minutes).
After a successful reboot I downloaded the interbench latency benchmark, ran it, and got the following result:
$ sudo ./interbench
894132 loops_per_ms read from file interbench.loops_per_ms
Creating file for read load…
Using 894132 loops per ms, running every load for 30 seconds
Benchmarking kernel 2.6.20-15-lowlatency at datestamp 200705182151
— Benchmarking simulated cpu of Audio in the presence of simulated —
Load Latency +/- SD (ms) Max Latency % Desired CPU % Deadlines Met
None 0.034 +/- 0.0966 0.961 100 100
Video 0.017 +/- 0.0504 0.897 100 100
X 1.56 +/- 3.28 10 100 100
Burn 0.011 +/- 0.0162 0.117 100 100
Write 0.037 +/- 0.103 1.31 100 100
Read 0.029 +/- 0.0886 1.99 100 100
Compile 0.101 +/- 0.651 9.4 100 100
Memload 0.044 +/- 0.164 2.02 100 100
— Benchmarking simulated cpu of Video in the presence of simulated —
Load Latency +/- SD (ms) Max Latency % Desired CPU % Deadlines Met
None 0.016 +/- 0.0512 0.929 100 100
X 3.39 +/- 8.42 66.7 99.6 86.3
Burn 0.019 +/- 0.0826 2.01 100 100
Write 0.345 +/- 2.06 25.7 100 99.2
Read 0.031 +/- 0.0624 1.07 100 100
Compile 0.177 +/- 1.68 26.7 100 99.5
Memload 0.114 +/- 1.24 28.4 100 99.6
— Benchmarking simulated cpu of X in the presence of simulated —
Load Latency +/- SD (ms) Max Latency % Desired CPU % Deadlines Met
None 0.222 +/- 1.08 8 93.8 91.3
Video 13 +/- 27 80 34.6 27
Burn 0.126 +/- 0.739 6 95.9 93.8
Write 1.4 +/- 6.01 53 87.1 82
Read 0.976 +/- 10 168 84 81.7
Compile 0.556 +/- 4.5 64 90.6 88
Memload 0.926 +/- 3.47 22 89.5 83.6
— Benchmarking simulated cpu of Gaming in the presence of simulated —
Load Latency +/- SD (ms) Max Latency % Desired CPU
None 3.29 +/- 4.79 34.4 96.8
Video 133 +/- 137 226 42.9
X 189 +/- 323 1555 34.6
Burn 386 +/- 417 454 20.6
Write 137 +/- 178 983 42.1
Read 68 +/- 73.7 140 59.5
Compile 526 +/- 593 1342 16
Memload 24.8 +/- 40.8 183 80.1
Well the audio test results look really nice, but the others seem way off. I don’t know if this is going to work nicely.
I then installed jack
$ sudo apt-get install jackd
Now I only need to test it with some audio applications…. Later.
UPDATE: After installing the low latency patch and playing around with Bristol Synthesiser I found the performance of the kernel to less than stellar. It seems like I might have to fool around with the realtime kernel.
Writing VHDL with Ubuntu Linux
First install ghdl and gtkwave:
$ sudo apt-get install ghdl gtkwave
See the fine http://ghdl.free.fr/ghdl/index.html for the rest
Remember to compile with the “–ieee=synopsys -fexplicit” option if you want to use non-standard packages, such as std_logic_arith.
You can also compile a whole project. First compile all the files to a executable named work:
$ ghdl -i --ieee=synopsys -fexplicit --workdir=work *.vhdl
Then make the design
$ ghdl -m --ieee=synopsys -fexplicit --workdir=work name_of_design
You can then run the design
$ ghdl ./name_of_design
Which is great for testing.
Happy testing.
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The Nintendo Wii
I think the Nintendo Wii will be a really nice console…
http://wii.nintendo.com/iwata_asks_vol1_p1.html
Cheap, small, silent and fun.
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Setting up a wiki for the dormitory
This guide is very brief and only ment for myself
I decided it was time to setup a server running Ubuntu Linux for my dormitory. I found an old pc in the dumpster abd installed Ubuntu Linux 6.06 from the server iso found at klid.dk.
I logged on to the server and installed the ssh-server
mac@v310-webserver:~$ sudo apt-get install ssh
I then edited the file /etc/apt/sources.list and included the security update repos. I then updated system by executing
mac@v310-webserver:~$ sudo apt-get update; sudo apt-get upgrade
I was now ready to get the wiki software. I dowloaded mediawiki
mac@v310-webserver:~$ wget http://heanet.dl.sourceforge.net/sourceforge/wikipedia/mediawiki-1.7.1.tar.gz
I extracted the file
mac@v310-webserver:~$ tar -xvzf mediawiki-1.7.1.tar.gz
Moved the files to a more appropriate place
mac@v310-webserver:~$ sudo mv mediawiki-1.7.1 /var/www/
Created a symbolic link to get a nicer path name
mac@v310-webserver:~$ sudo ln -s /var/www/mediawiki-1.7.1/ /var/www/wiki Made the config directory writable
mac@v310-webserver:~$ sudo chmod 777 /var/www/wiki/config
Now I had to create a MySQL database and user to continue. I sat the root password
mac@v310-webserver:~$ mysqladmin -u root password mysecretpass I created a MySQL wiki user and a wiki database
mac@v310-webserver:~$ mysql -u root -p mysql
create database wikiDB;
grant create, select, insert, update, delete, lock tables on wikiDB.* to wiki@localhost identified by 'password'; q
I then uploaded then configuration file to the server
mac@v310-webserver:~$ mv /var/www/wiki/config/LocalSettings.php /var/www/wiki
And presto!
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Ny internetudbyder
Vi skal skifte udbyder på vores kollegie. Efter lang tid med en ustabil router, der dør konstant og skal genstartes, har vi besluttet os for at skifte væk fra Tele2. Tele2′s support har været under al kritik og jeg kan ikke anbefale dem. Vi havde en erhvervs aftale, som man burde tror ville give os ret til at vi havde en oppetid på mere end 1 1/2 døgn, men det var de ikke enige i. Vi har på dårlige dage ikke engang kunne holde routeren oppe i mere end et kvarter af gangen 
Nå men så har jeg set på hvilke andre muligheder der er. Jeg blev fortalt af en med kollegianer, at man kunne få 20/20 Mbit WiMax for 400 kr. om måneden hos orza.dk, men ved nærmere eftersyn har jeg fundet ud af at bagmanden har en noget blakket fortid. Prøv bare at søge på Basse Bergqvist på worldonline.dk eller google. Han har bl.a. stået bag dixa.net, som gik konkurs med et brag , han er desuden blevet efterforsket af politiet i to år for svindel og tyveri. Manden er bevares ikke blevet dømt, men jeg tør ikke stole på et nystartet firma, hvor der er bare den mindste tvivl om hvorvidt det er seriøst.
Jeg har i stedet set på tdc’s erhvervs ADSL. Priserne er ikke fantastiske, men hellere ikke helt urimelige. Jeg har tidligere haft erfaring med at de er de “mindst” dårlige bl.a. mange udbydere, så vi bliver nok nødt til at ty til dem, selv om jeg ikke er glad for at støtte så store “monopoler”.
Jeg har også set på Webpartner, men de er desværre ikke gode til at oplyse deres priser, så jeg skal først have ringet til dem, førend at jeg kan tage stilling til dem.
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Othello java game
I’ve made a game in java together with three other guys from DTU. The game is configured to start with java webstart, so you need to have java 1.5 installed. Choose javaws, If your browser asks about which program to use for opening the file.
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nslu2 guide
Wow I’ve just created my first wiki entry on www.nslu2-linux.org. It’s a guide on how to build packages with Ubuntu Breezy for an DS-101g+. The reason i wrote it is, that one of my friends from the university bought a DS-101g+ NAS box, and wanted to install a lot of extra applications on it. Unfortunately all of the installation packages hadn’t been compiled for the powerpc architecture. I had offered to help him, so I figured out how to compile the packages, and wrote a little guide that he could follow. The wiki entry can be found here
(this post was originally from mcdonnell.dk, posted at Thursday, August 18th, 2005)
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